I would contact ID and ask them what frequency they cross the tweeters over at in the passive network. That way you’ll know exactly what your target frequency for it would be to get in the middle of the ballpark for running active, no guessing involved.
The Fi N.7 has fantastic specifications and should sound great. I can’t wait to play with a set in person. The SSA Evil 6.5” mid sounds very good and is a great bargain at the price they ask for them. My set made me very happy while my brother in law was demoing them in his car. I’m really looking forward to the opportunity to finally get them installed in mine. The mids will be the toughest decision simply because you can’t just listen to them all somewhere. To make the decision even harder (lol) I suggest taking a look through the lists of drivers available at Parts Express and Madisound. The raw drivers at those stores are a great place to start if you were interested in going that route. I know exactly what you are referring to on the sound of your old mids. As much as I love my Fi and SSA equipment I have to say that one of the best drivers I’ve heard that fits that description to a “T” is the Peerless HDS 830875. I gave a set I bought used to my brother in law for his build and after we got everything installed and tuned I wish I had kept them!! Super smooth, warm response that brought out the finest details with ease. They should definitely be on your list of equipment to consider.
Your assumption on the difference between regular woofers/mids and the PA drivers is pretty well spot on. While PA speakers “CAN” sound good very very few will right out of the box and even with a great EQ at your disposal the vast majority of them will excel at getting loud and still never sound that good. Most need an enclosure, a ported one even better, to get remotely usable midbass and without that a warmer response will be difficult to obtain
J is right though, you can always save up and buy the different parts of your equipment as you can and piece it together. I’m in the middle of doing so for my Grand Prix right now. I had the Evil mids, got the Evil tweeters a few months ago, a pair of SSA F8L 8” subs a little over a month ago, just picked up a pair of SSA IC150.4 amps a couple of weeks ago and got my JL TWK88 DSP last week. I’m working my way towards getting the IC2200.1 and while right now I have a pair of SSA DCON subs as well to help complete an all SSA system I have been piecing this together for awhile now.
The crossovers and such you’re looking at are okay but I’m very honestly saying that they’re a waste in comparison to any decent DSP. The plethora of settings available in just one controller is mind blowing and kinda addictive, lol. Multiple bands, up to 31 bands of graphic and/or parametric EQ per each channel. Crossovers that can be set to any frequency(ies) you want, high pass, low pass and bandpass, from -6dB to -48dB slopes per channel, and oftentimes selectable between linkwitz-Riley, Butterworth, etc curves. Time alignment, individual channel gain controls, phase switching, and more all can be found available in the decent DSP’s available today. They’re an investment that you can use for years to come in any build you end up doing. The miniDSP is very budget friendly and very powerful for the price. The only thing people see as a drawback is the limited 2V RCA outputs, which if those folks were in the know doesn’t mean anything.
No one minds you making long posts. Trust me it’s a welcome sight to the sore eyes around here and the typical, “I just wanna bang as loud as I can so which one is better, sub X or sub Y?” lol That’s not the norm for around here but we don’t seldom see posts with questions with quite this much information. It’s refreshing in my honest opinion so keep it up!